1 | /* |
2 | * Copyright (c) 2012-2014 Glen Joseph Fernandes |
3 | * glenfe at live dot com |
4 | * |
5 | * Distributed under the Boost Software License, |
6 | * Version 1.0. (See accompanying file LICENSE_1_0.txt |
7 | * or copy at http://boost.org/LICENSE_1_0.txt) |
8 | */ |
9 | #ifndef BOOST_SMART_PTR_DETAIL_ARRAY_ALLOCATOR_HPP |
10 | #define BOOST_SMART_PTR_DETAIL_ARRAY_ALLOCATOR_HPP |
11 | |
12 | #include <boost/align/align.hpp> |
13 | #include <boost/smart_ptr/detail/array_traits.hpp> |
14 | #include <boost/smart_ptr/detail/array_utility.hpp> |
15 | #include <boost/type_traits/alignment_of.hpp> |
16 | |
17 | namespace boost { |
18 | namespace detail { |
19 | struct ms_init_tag { }; |
20 | struct ms_noinit_tag { }; |
21 | |
22 | template<class T> |
23 | struct ms_allocator_state; |
24 | |
25 | template<class T> |
26 | struct ms_allocator_state<T[]> { |
27 | typedef typename array_base<T>::type type; |
28 | |
29 | ms_allocator_state(std::size_t size_, |
30 | type** result_) |
31 | : size(size_ * array_total<T>::size), |
32 | result(result_) { |
33 | } |
34 | |
35 | std::size_t size; |
36 | |
37 | union { |
38 | type** result; |
39 | type* object; |
40 | }; |
41 | }; |
42 | |
43 | template<class T, std::size_t N> |
44 | struct ms_allocator_state<T[N]> { |
45 | typedef typename array_base<T>::type type; |
46 | |
47 | ms_allocator_state(type** result_) |
48 | : result(result_) { |
49 | } |
50 | |
51 | enum { |
52 | size = array_total<T[N]>::size |
53 | }; |
54 | |
55 | union { |
56 | type** result; |
57 | type* object; |
58 | }; |
59 | }; |
60 | |
61 | template<class A, class T, class R> |
62 | class as_allocator |
63 | : public A { |
64 | template<class A_, class T_, class R_> |
65 | friend class as_allocator; |
66 | |
67 | #if !defined(BOOST_NO_CXX11_ALLOCATOR) |
68 | typedef std::allocator_traits<A> AT; |
69 | typedef typename AT::template rebind_alloc<char> CA; |
70 | typedef typename AT::template rebind_traits<char> CT; |
71 | #else |
72 | typedef typename A::template rebind<char>::other CA; |
73 | #endif |
74 | |
75 | public: |
76 | typedef A allocator_type; |
77 | |
78 | #if !defined(BOOST_NO_CXX11_ALLOCATOR) |
79 | typedef typename AT::value_type value_type; |
80 | typedef typename AT::pointer pointer; |
81 | typedef typename AT::const_pointer const_pointer; |
82 | typedef typename AT::void_pointer void_pointer; |
83 | typedef typename AT::const_void_pointer const_void_pointer; |
84 | typedef typename AT::size_type size_type; |
85 | typedef typename AT::difference_type difference_type; |
86 | #else |
87 | typedef typename A::value_type value_type; |
88 | typedef typename A::pointer pointer; |
89 | typedef typename A::const_pointer const_pointer; |
90 | typedef typename A::size_type size_type; |
91 | typedef typename A::difference_type difference_type; |
92 | typedef typename A::reference reference; |
93 | typedef typename A::const_reference const_reference; |
94 | typedef void* void_pointer; |
95 | typedef const void* const_void_pointer; |
96 | #endif |
97 | |
98 | template<class U> |
99 | struct rebind { |
100 | #if !defined(BOOST_NO_CXX11_ALLOCATOR) |
101 | typedef as_allocator<typename AT:: |
102 | template rebind_alloc<U>, T, R> other; |
103 | #else |
104 | typedef as_allocator<typename A:: |
105 | template rebind<U>::other, T, R> other; |
106 | #endif |
107 | }; |
108 | |
109 | typedef typename array_base<T>::type type; |
110 | |
111 | as_allocator(const A& allocator_, type** result) |
112 | : A(allocator_), |
113 | data(result) { |
114 | } |
115 | |
116 | as_allocator(const A& allocator_, std::size_t size, |
117 | type** result) |
118 | : A(allocator_), |
119 | data(size, result) { |
120 | } |
121 | |
122 | template<class U> |
123 | as_allocator(const as_allocator<U, T, R>& other) |
124 | : A(other.allocator()), |
125 | data(other.data) { |
126 | } |
127 | |
128 | pointer allocate(size_type count, const_void_pointer = 0) { |
129 | enum { |
130 | M = boost::alignment_of<type>::value |
131 | }; |
132 | std::size_t n1 = count * sizeof(value_type); |
133 | std::size_t n2 = data.size * sizeof(type); |
134 | std::size_t n3 = n2 + M; |
135 | CA ca(allocator()); |
136 | void* p1 = ca.allocate(n1 + n3); |
137 | void* p2 = static_cast<char*>(p1) + n1; |
138 | (void)boost::alignment::align(align: M, size: n2, ptr&: p2, space&: n3); |
139 | *data.result = static_cast<type*>(p2); |
140 | return static_cast<value_type*>(p1); |
141 | } |
142 | |
143 | void deallocate(pointer memory, size_type count) { |
144 | enum { |
145 | M = boost::alignment_of<type>::value |
146 | }; |
147 | std::size_t n1 = count * sizeof(value_type); |
148 | std::size_t n2 = data.size * sizeof(type) + M; |
149 | char* p1 = reinterpret_cast<char*>(memory); |
150 | CA ca(allocator()); |
151 | ca.deallocate(p1, n1 + n2); |
152 | } |
153 | |
154 | const A& allocator() const { |
155 | return static_cast<const A&>(*this); |
156 | } |
157 | |
158 | A& allocator() { |
159 | return static_cast<A&>(*this); |
160 | } |
161 | |
162 | void set(type* memory) { |
163 | data.object = memory; |
164 | } |
165 | |
166 | void operator()() { |
167 | if (data.object) { |
168 | R tag; |
169 | release(tag); |
170 | } |
171 | } |
172 | |
173 | private: |
174 | void release(ms_init_tag) { |
175 | #if !defined(BOOST_NO_CXX11_ALLOCATOR) |
176 | as_destroy(allocator(), data.object, data.size); |
177 | #else |
178 | ms_destroy(data.object, data.size); |
179 | #endif |
180 | } |
181 | |
182 | void release(ms_noinit_tag) { |
183 | ms_destroy(data.object, data.size); |
184 | } |
185 | |
186 | ms_allocator_state<T> data; |
187 | }; |
188 | |
189 | template<class A1, class A2, class T, class R> |
190 | bool operator==(const as_allocator<A1, T, R>& a1, |
191 | const as_allocator<A2, T, R>& a2) { |
192 | return a1.allocator() == a2.allocator(); |
193 | } |
194 | |
195 | template<class A1, class A2, class T, class R> |
196 | bool operator!=(const as_allocator<A1, T, R>& a1, |
197 | const as_allocator<A2, T, R>& a2) { |
198 | return a1.allocator() != a2.allocator(); |
199 | } |
200 | |
201 | template<class T, class Y = char> |
202 | class ms_allocator; |
203 | |
204 | template<class T, class Y> |
205 | class ms_allocator { |
206 | template<class T_, class Y_> |
207 | friend class ms_allocator; |
208 | |
209 | public: |
210 | typedef typename array_base<T>::type type; |
211 | |
212 | typedef Y value_type; |
213 | typedef Y* pointer; |
214 | typedef const Y* const_pointer; |
215 | typedef std::size_t size_type; |
216 | typedef std::ptrdiff_t difference_type; |
217 | typedef Y& reference; |
218 | typedef const Y& const_reference; |
219 | |
220 | template<class U> |
221 | struct rebind { |
222 | typedef ms_allocator<T, U> other; |
223 | }; |
224 | |
225 | ms_allocator(type** result) |
226 | : data(result) { |
227 | } |
228 | |
229 | ms_allocator(std::size_t size, type** result) |
230 | : data(size, result) { |
231 | } |
232 | |
233 | template<class U> |
234 | ms_allocator(const ms_allocator<T, U>& other) |
235 | : data(other.data) { |
236 | } |
237 | |
238 | pointer allocate(size_type count, const void* = 0) { |
239 | enum { |
240 | M = boost::alignment_of<type>::value |
241 | }; |
242 | std::size_t n1 = count * sizeof(Y); |
243 | std::size_t n2 = data.size * sizeof(type); |
244 | std::size_t n3 = n2 + M; |
245 | void* p1 = ::operator new(n1 + n3); |
246 | void* p2 = static_cast<char*>(p1) + n1; |
247 | (void)boost::alignment::align(align: M, size: n2, ptr&: p2, space&: n3); |
248 | *data.result = static_cast<type*>(p2); |
249 | return static_cast<Y*>(p1); |
250 | } |
251 | |
252 | void deallocate(pointer memory, size_type) { |
253 | void* p1 = memory; |
254 | ::operator delete(p1); |
255 | } |
256 | |
257 | #if defined(BOOST_NO_CXX11_ALLOCATOR) |
258 | pointer address(reference value) const { |
259 | return &value; |
260 | } |
261 | |
262 | const_pointer address(const_reference value) const { |
263 | return &value; |
264 | } |
265 | |
266 | size_type max_size() const { |
267 | enum { |
268 | N = static_cast<std::size_t>(-1) / sizeof(Y) |
269 | }; |
270 | return N; |
271 | } |
272 | |
273 | void construct(pointer memory, const_reference value) { |
274 | void* p1 = memory; |
275 | ::new(p1) Y(value); |
276 | } |
277 | |
278 | void destroy(pointer memory) { |
279 | (void)memory; |
280 | memory->~Y(); |
281 | } |
282 | #endif |
283 | |
284 | void set(type* memory) { |
285 | data.object = memory; |
286 | } |
287 | |
288 | void operator()() { |
289 | if (data.object) { |
290 | ms_destroy(data.object, data.size); |
291 | } |
292 | } |
293 | |
294 | private: |
295 | ms_allocator_state<T> data; |
296 | }; |
297 | |
298 | template<class T, class Y1, class Y2> |
299 | bool operator==(const ms_allocator<T, Y1>&, |
300 | const ms_allocator<T, Y2>&) { |
301 | return true; |
302 | } |
303 | |
304 | template<class T, class Y1, class Y2> |
305 | bool operator!=(const ms_allocator<T, Y1>&, |
306 | const ms_allocator<T, Y2>&) { |
307 | return false; |
308 | } |
309 | |
310 | class ms_in_allocator_tag { |
311 | public: |
312 | void operator()(const void*) { |
313 | } |
314 | }; |
315 | } |
316 | } |
317 | |
318 | #endif |
319 | |